title: Matrix solid phase dispersion assisted enzymatic hydrolysis as a novel approach for cocaine and opiates isolation from human hair.
abstract: The possibility of assisting enzymatic hydrolysis (EH) procedures by sample disruption mechanisms inherent to matrix solid phase dispersion (MSPD) has been explored in the current study. EH of hair specimens from poly-drug abusers was assisted by dispersing/blending the sample (0.05 g) with alumina (2.25 g) before loading the dissolved enzyme (6 mL of 1 mg mL(-1) Pronase E in 1.4 M/1.4 M Tris/HCl, pH 7.3) through the hair-alumina solid phase packaged inside a disposable MSPD syringe. The MSPD-EH method was developed, and it proved to offer quantitative results when isolating cocaine, benzoylecgonine (BZE), codeine, morphine and 6-monoacethylmorphine (6-MAM) from human hair samples. The procedure allows an on column clean-up/pre-concentration procedure of the isolated targets by attaching a previously conditioned Oasis HLB cartridge to the end of the MSPD syringe. The EH procedure of human hair with Pronase E can therefore be shortened to approximately 30 min. Within this time, sample blending/dispersion, MSPD syringe package, elution (EH when dissolved Pronase E is passing through the sample-dispersant bed), and extract clean-up and target pre-concentration stages are achieved. Gas chromatography-mass spectrometry (GC-MS) was used for determining each target after elution from the Oasis HLB cartridges with 2 mL of 2% (v/v) acetic acid in methanol, concentration by N2 stream evaporation, and dried extract derivatization with N-methyl-tert-butylsilyltrifluoroacetamide (BSTFA) and chlorotrimethylsilane (TMCS). The method was validated according to the guidance for bioanalytical method validation of the US Department of Health and Human Services, Food and Drug Administration. The simplicity of the proposed approach makes it a useful procedure for screening/quantifying drugs of abuse in hair specimens from poly-drug abusers.
authors.affiliation: Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n, 15782 Santiago de Compostela, Spain.
authors.forename: Martha
authors.initials: M
authors.lastname: Míguez-Framil
authors.forename: Pamela
authors.initials: P
authors.lastname: Cabarcos
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: Tabernero
authors.forename: Ana María
authors.initials: AM
authors.lastname: Bermejo
authors.forename: Pilar
authors.initials: P
authors.lastname: Bermejo-Barrera
authors.forename: Antonio
authors.initials: A
authors.lastname: Moreda-Piñeiro
mesh_terms: D003042:Cocaine / Q000032:analysis / Q000302:isolation & purification*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006197:Hair / Q000737:chemistry*; D006801:Humans; D006868:Hydrolysis; D013287:Illicit Drugs / Q000032:analysis*; D009022:Morphine Derivatives / Q000032:analysis / Q000302:isolation & purification*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D052616:Solid Phase Extraction / Q000379:methods*
chemical_list: D013287:Illicit Drugs; D009022:Morphine Derivatives; D003042:Cocaine
keywords: Drugs of abuse; Gas chromatography–mass spectrometry; Human hair; Matrix solid phase dispersion assisted enzymatic hydrolysis